Activation of 2-Aminoanthracene by Cell-Free Microbial Extracts

The activation of the precarcinogen 2-aminoanthracene was investigated employing cell-free extracts of Escherichia coil, Pseudomonas aeruginosa, Streptococcus faecalis, Bacteroides fragilis, Clostridium perfringens and the eukaryote Candida albicans. A modification of the Salmonella typhimurium/mammalian microsomal mutagenicity assay was employed to determine activation. Of the species tested, only cell-free extracts of Escherichia coli and Bacteroides fragilis failed to induce the reversion of the Salmonella typhimurium his- mutants TA-98 and/or TA-100 to his+ revertants. Separation of the cytosol and membrane pellet enzymes was completed. Of the organisms tested only the membrane pellet enzymes of Clostridium perfringens showed activation of 2-aminoanthracene

Studies of stratospheric particulates

A sophisticated computer model of polar stratospheric clouds was developed and used to study the properties of ice clouds. The model has recently been extended to investigate nitric acid clouds and ice clouds as well as their interactions with stratospheric gases. The model is now being applied to interpret data collected during recent expeditions to the Antarctic and the Arctic. Some work has also been done to understand the properties of noctilucent clouds and their implications for the chemistry and dynamics of the upper stratosphere

Mortality from head injury over four decades in Scotland

Although the causes of head injury, the population at risk and approaches to prevention and treatment are continually evolving, there is little information about how these are reflected in patterns of mortality over time. We used population based comprehensive data uniquely available in Scotland to investigate changes in the total numbers of deaths from 1974 to 2012, as well as the rates of head injury death, from different causes, overall and in relation to age and gender. Total mortality fell from an annual average of 503 to 339 with a corresponding annual decrease in rate from 9.6 to 6.4 per 100,000 population, the decline substantially occurring between 1974 and 1990. Deaths in children fell strikingly but rose in older people. Deaths in males fell to a greater extent than females but remained at a higher rate overall. Initially, a transport accident accounted for most deaths but these fell by 80%, from 325 per year to 65 per year over the 39 year period. Deaths from falling and all other causes did not decline, coming to outnumber transport accident deaths by 1998, which accounts for the overall absence of change in total mortality in recent years. In order to reduce mortality in the future, more effective measures to prevent falls are needed and these strategies will vary in younger adults (where alcohol is often a factor), and in older adults where infirmity can be a cause. In addition, measures to sustain reductions in transport accidents need to be maintained and further developed

Advanced Refrigerator/Freezer Technology Development. Technology Assessment

The NASA Lewis Research Center, through contract with Oceaneering Space Systems, is engaged in a project to develop advanced refrigerator/freezer (R/F) technologies for future Life and Biomedical Sciences space flight missions. The first phase of this project, a technology assessment, has been completed to identify the advanced R/F technologies needed and best suited to meet the requirements for the five R/F classifications specified by Life and Biomedical Science researchers. Additional objectives of the technology assessment were to rank those technologies based on benefit and risk, and to recommend technology development activities that can be accomplished within this project. This report presents the basis, the methodology, and results of the R/F technology assessment, along with technology development recommendations

Atmospheric science

The following types of experiments for a proposed Space Station Microgravity Particle Research Facility are described: (1) growth of liquid water drop populations; (2) coalescence; (3) drop breakup; (4) breakup of freezing drops; (5) ice nucleation for large aerosols or bacteria; (6) scavenging of gases, for example, SO2 oxidation; (7) phoretic forces, i.e., thermophoresis versus diffusiophoresis; (8) Rayleigh bursting of drops; (9) charge separation due to collisions of rimed and unrimed ice; (10) charged drop dynamics; (11) growth of particles in other planetary atmospheres; and (12) freezing and liquid-liquid evaporation. The required capabilities and desired hardware for the facility are detailed

Using Fine Resolution Orthoimagery and Spatial Interpolation to Rapidly Map Turf Grass in Suburban Massachusetts

This paper explores the use of spatial interpolative methods in conjunction with object based image analysis to estimate turf grass land cover quantity and allocation in Greater Boston, Massachusetts, USA. The goal is to learn how accurately turf grass can be estimated if only a limited portion of the study area is mapped. First, turf grass land cover is mapped at the 0.5 m resolution across the entire Plum Island Ecosystems (PIE) Long Term Ecological Research (LTER) site, a 1143-km2 area. Second, the turf grass map is aggregated into 120 m cells (N = 84,661). Third, a random sample of these 120 m cells are selected to generate an estimate of the unselected cells using four estimation methods - Inverse Distance Weighting, Kriging, Polygonal Interpolation, and Mean Estimation. The difference between known and estimated values is recorded using 120 m cell and census block group stratifications. This process is repeated 500 times for sample sizes of 2.5%, 5.0%, 7.5% and 10.0% of the study area, for a total of 2000 iterations. The average error statistics are reported by sample size, strata, and estimation method. Inverse distance weighting performed best in terms of total error across all sample sizes. It was found that by mapping only 2.5% of the study area, all four methods outperformed a recently published approach to estimating turf grass in terms of overall error